The present application relates to a method and to an apparatus for detecting various panel conditions. Examples of such panel conditions described below includes various physical conditions of a structural panel such as an aircraft wing; various conditions of a window panel; the presence or absence of an object on a floor panel (e.g., in a space monitor); and the presence and location of pressure applied (e.g., by a stylus) to a touch panel.
The present application is related to: International Application PCT/IL00/00241 published Nov. 9, 2000 as International Publication No. WO 00/67013; International Application PCT/IL02/00854 filed Oct. 24, 2002, Published May 1, 2003 as International Publication No. WO 03/036321; International Application PCT/IL02/00983, filed Dec. 5, 2002, published Jun. 12, 2003 as International Publication No. WO 03/048668; and U.S. Pat. No. 6,621,278 issued Sep. 16, 2003, the contents of which applications and patent are incorporated herein by reference in their entirety.
The above-cited applications and patent relate to methods and apparatus for measuring, with extremely high sensitivity, various parameters having a known or determinable relationship with respect to the transit time of an energy wave (electromagnet or sonic) through a medium (solid, liquid or gas). Briefly, this is done by transmitting through the medium a cyclically-repeating energy wave; receiving the energy wave transmitted through the medium; detecting a predetermined fiducial point in the received energy wave; continuously changing the frequency of the transmission of the energy wave in accordance with the detected fiducial point of each received energy wave such that the number of waves received is a whole integer; and measuring the changes in frequency to produce a measurement of changes in transit time of the energy wave from the transmitter to the receiver, and thereby a measurement of the predetermined parameter.
The above-cited applications and patent described many implementations of such method and apparatus in many fields, both medical and non-medical, for detecting or measuring various conditions with an extremely high degree of sensitivity.